Cows, you see, have a serious emissions problem. To digest tough plant material, their cavernous stomachs act as fermentation vats. They’re teeming with methanogens, microbes that process cellulose to make volatile fatty acids, which the cows turn into meat and milk. But those methanogens also produce methane, a particularly nasty greenhouse gas that is 80 times more potent than carbon dioxide, thanks to the way its molecules vibrate to absorb infrared radiation. These gases capture heat, and that means more global warming…

Now multiply those burps by the world’s huge cattle population. To satisfy humanity’s bottomless appetite for beef and milk, a billion head of cattle now roam the planet. A paper published in September in the journal Nature Food by an international team of researchers found that the global food system generates a staggering 35 percent of total greenhouse gas emissions. Beef is responsible for a quarter of those food emissions, with another 8 percent coming from milk production…

If scientists can figure out how to get cows to stop belching so much, that would make a big dent in emissions, and we’d see the climate effects almost immediately. So Mitloehner and other researchers are experimenting with food additives like seaweed, garlic, and even essential oils derived from plants like coriander seed, which tweak the animals’ gut environment in different ways, for instance by disrupting the enzymes that produce methane.

RTFA. Lots about hows and whys of the difficulties coming up with a solution to the problem. Beaucoup detail about the inventive constructs researchers come up with to measure the methane output…and what they’ve tried, so far, in attempts to mitigate that production.